Characterization of Genetic Modifiers of Estrogen-Induced Mammary Cancer
Abstract
Prolonged exposure to estrogens is considered a major risk factor for development of breast cancer; When treated with estrogen for 28 weeks, ACI rats develop mammary cancers in over 90% of the population at risk. Genetic crosses between the susceptible ACI rat and resistant Copenhagen (COP) or Brown Norway (BN) rats identified a region on chromosome 5 (Emcal) t!%at modified the development of estrogen-induced mammary cancer. To define the role of Emcal in the development of estrogen-induced mammary cancer, a congenic line has been developed (ACI.BN-Emcal) in which the resistant BN allele of Emcal has been introgressed onto an ACI background. Female ACI.BN-Emcal rats treated with estrogen for 28 weeks exhibit a significant decrease in the incidence of mammary cancer in the population at risk, a significant delay in the latency to the development of mammary cancer, and a significant decrease in the number of tumors per rat compared to ACI rats. These data suggest that Emcal is a strong modifier of estrogen-induced mammary cancer. Additional congenic lines, in which the Emcal locus has been divided into smaller regions, have been generated and will be used to further define the region(s) on chromosome 5 and to identify more precisely the gene(s) that modify estrogen-induced mammary cancer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2004
- Accession Number
- ADA428943
Entities
People
- Beverly S. Schaffer
Organizations
- University of Nebraska Medical Center